Can spraying WD40 into an electric fan motor damage the motor?

Question

A mobile RV repair guy tried to fix my RV AC by spraying WD40 on the fan motor bushings AND into the motor itself (where the windings are). A few days later and the motor doesn t run, it just gets really really hot.

Answer 1

No.

It was a very short term fix. Enough to tell him it was the "bushings". Not a different problem elsewhere. When it needs bushings it is cheaper JUST TO BUY ANOTHER MOTOR. It is that much of a hassle to repair that, that they DON'T.! Just grab a new motor off the shelf and swap out.

. There are millions of extra motors sitting on a shelf somewhere, waiting to be used.When I say new I mean still in the original packaging. Unused.

. When it is getting really hot, that means the electricity is going through it but it won't spin to cool itself off. It is buggered. No amount of praying is going to fix something that will not HEAL ITSELF, so get off of your knees and get another unit installed. Or the rest of your year will be either hot Hell or Cold Hell(depending on what that fan motor does). Fan motors generally move the air from the heating or cooling device. 1 fan for 2 operations. So basically works 365 day per year...day & night. so yes, they will eventually wear out.

. What happens is that the weight of the motor eventually makes a channel in the round bushing. The bushing holds the armature(the moving part in the center) of the windings field(which is the part that does not move or outer casing) Once it is oval the armature rubs on the field magnets (which essentially work like drum brakes in a car.) The none moving part stops the moving part. There is damage to the armature and to the windings."its coating is exposed and it shorts out killing it" as everything becomes unbalanced.

It is more info than you needed to know but that is what is happening.

Replace as the other is now a boat anchor...or door stop. If it is a big motor, they might recycle it, meaning they give you money for it. A "motor rewind shop" is who I would check the yellow pages for as they would know if THEY OR SOMEONE does recycling of that material. If the fan motor is the size that can be grabbed with one hand, then that is generally pitched. Being an RV it is probably small one.

Handiman 30+y

Answer 2

Disconnect the fan, Now. Most have a thermal overload but a Chinees job might not.



The Water-Displacement Formula 40? Not in itself, no.

But, it can drive outside dirt into the bushings, or drive out what lube is left. Bushings are often permanently-lubed sintered-bronze, better no lube than dirt forced in.

It cannot damage windings. They are heavy formvar, good for 400 degrees. Only very old shellacked windings from something from 19th century would be damaged. Unless they had been overheated, anyway, and were ready to go.

Do as others suggest, take it apart , lube bushings, see if armature rubbing.

Answer 3

If the bushings needed lubrication the motor is old and needs replacing. Get a new one before you burn up your RV.

Answer 4

WD40 is flammable, and it would burn where brushes spark and carry high current. Burning would possibly remove insulating varnish from wires, shorting them out, thus ruining the motor.

Answer 5

It electrically shorted out. You may need a

New fan motor.

Answer 6

Wrong thing to do but the motor was probably junk anyway.

Answer 7

WD-40 is a short term fix. the silicone component doesn't last at all. You need a proper lubricant.

Answer 8

My guess is that the whatever problem necessitated spraying the WD40 in the first place is the problem that got worse and seized the motor. It's very unlikely that the WD40 had anything to do with the failure.

Answer 9

The bushing needs lubricant. WD40 is mostly solvent that does a very poor job of lubricating.

Answer 10

Isn't WD40 a cleaner more than a lubricant? Shouldn't he had sprayed lube in there too, after running it with the WD40 for a bit?

Answer 11

Do not use WD40 on an electrical device. WD40 will collect dust over time. Use a dedicate electrical cleaner such as CRS Quick Dry Electronic Cleaner. You can buy it at Walmart and almost any auto or hardware store. https://www.amazon.com/CRC-05103-Electronic-Cleaner-11/dp/B000BXOGNI?psc=1&SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=duckduckgo-osx-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=B000BXOGNI

Answer 12

Moisture leads to insulation failure in motors which also cause overheating.

Best chance to recover the motor is to dry the windings and rotor.

Answer 13

Take the motor out and take it apart. You will likely have to drill out some rivets. Clean the shaft and the bushings and put a drop of light oil on each bushing.



If the bushing wears it often lets the armature touch the field magnets. Then the motor can't start turning even if the bushings are slippery.



Many fan motors were able to be lubricated through a hole, in decades past, but I have no idea how those motors are built nowadays.



WD-40 is not exactly a lubricant. It's not exactly a penetrating oil either. It flushes things out. Like dirt and probably lubrication.



-General automotive mechanic since 1972

Answer 14

WD40 is about the worst lube for any electric motor.



I tried it in a range hood fan and it kept seizing up. What I ended up using for a lubricant was 10W30 motor oil. That was 2 years ago and the fan is used virtually every day on HIGH with NO ISSUES.



NEVER USE A PENETRATING OIL ON MOTOR BEARINGS.

Answer 15

Not really, Yes likely the bearings were dry and stiff. There is No way to lubricate them from the outside "he is a knucklehead" Take it out and see if you can spin it by hand if it doesn't spin freely it is no good and what he did didn't matter. A McGuyver type may be able to open the motor up and get some lube in the bearings......if not replace it.

Answer 16

WD40 will not cause harm in this respect. It must have been close to failure or you wouldn't have engaged his services.